Enhancing packet aggregation performance in coexisting wireless networks

ABSTRACT

A wireless combination device is coupled to an antenna for communicating via a first wireless network. A second wireless transceiver configured for communication via said second wireless network. A packet aggregator is coupled to the first wireless transceiver configures a frame aggregated packet for at least a portion of activities on the first wireless network. The frame aggregated packet includes a plurality of data packets and a dummy packet or spoofing so that said frame aggregated packet is extended in time or indicates an extension sufficient to overlap a Tx time interval or Rx time interval for communications occurring over a second wireless network. The first wireless network and said second wireless network are overlapping networks.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of and claims priority to U.S. patentapplication Ser. No. 14/301,656, filed Jun. 11, 2014, which is aDivisional of and claims priority to U.S. patent application Ser. No.13/161,057, filed Jun. 15, 2011, which claims the benefit of ProvisionalApplication Ser. No. 61/355,584 entitled “MECHANISM TO ENHANCE PACKETAGGREGATION PERFORMANCE IN COEXISTING WIRELESS NETWORKS”, filed Jun. 17,2010. Said applications herein incorporated by reference in itsentirety.

FIELD

Disclosed embodiments are directed, in general, to wirelesscommunication systems and, more specifically, methods of operating inwireless networks having coexisting overlapping bands.

BACKGROUND

As wireless technologies proliferate, mobile wireless devicesincorporate a multiplicity of different wireless standards. For example,a cellular telephone can accommodate a cellular network (e.g., UniversalMobile Telecommunications System), a wireless local area network(“WLAN”), such as IEEE 802.11, and a wireless personal area network(“WPAN”) such as Bluetooth (BT). Including WPAN access makes utilizationof a wireless device more convenient by allowing use of wirelessheadsets and other short-range wireless appliances.

Some wireless networks occupy an adjacent or overlapping frequencyspectrum. For example, BT and IEEE 802.11b/g/n, and WiMax can utilizethe same 2.4-2.5 GHz band. Mobile wireless devices are sometimes capableof accessing multiple wireless networks, such as a cellular smart phonethat supports radios in overlapping RF bands (a combination device thatis referred to herein as a “combo device”).

Therefore, interference between these technologies operating in the samedevice creates challenges on the coexistence of these two wirelessinterfaces. More specifically, the out of band emission by eithertechnology may saturate the receiver of the other technology and hence,blocking may occur. The limited medium time available to each radio ismore problematic.

To solve the network coexistence problem in which WLAN is one of thesubsystems operating in the same combo device, time multiplexedoperation is used. For example, in the case of WLAN and BT coexistence,BT voice calls can take priority over other traffic flows in WLAN.During the time periods that the combo device operates in BT mode, theWLAN can operate in unscheduled automatic power saving delivery (U-APSD)mode. During the time that the combo device operates in WLAN mode, itsends a trigger frame (or a PS-Poll if legacy power save mode is used)to the access point (AP) indicating that it is ready to receive packets.

Regarding legacy PS mode, usually, the node/station (node/STA) tries tosend the PS-Poll frames immediately after the BT active gap is over,therefore increasing the chances that the AP will send a data frameduring the BT idle gap. However, depending on how congested the networkis, the AP may not be able to send the data frame during the BT activegap. Hence, the node/STA sends the clear to send (CTS2Self) frame toprotect from the avalanche effect. However, as described below, for longaggregated packets such as aggregated medium access control (MAC)protocol data unit (A-MPDU) packets, CTS2Self may become unreliable.

IEEE 802.11n technology can further complicate coexistence of WLAN andBT technology on combo devices. IEEE 802.11n allows multiple mediumaccess control (MAC) data frames to be carried in a single physicalframe (referred to as aggregation or an aggregate). There are two formsof frame aggregation: Aggregated MAC Protocol Data Unit (A-MPDU) andAggregated MAC Service Data Unit (A-MSDU). These aggregated packetscomprising a plurality of data frames have a larger size and occupy (forthe most part) a longer duration of time as compared to a single packettransmitted using IEEE 802.11g technology. Performance of IEEE 802.11nwith BT voice can degrade substantially, and can result in the combodevice being disconnected from the AP.

For example FIG. 1A depicts a known wireless network 100 including an APfor a first network shown as a WLAN AP 110 (hereafter AP), and a combodevice 120 identified as a STA1-BT master at a combo node. Combo device120 communicates over a second network that overlaps the first networkshown as BT to a BT slave 125 (e.g., an earpiece), and combo device 120communicates over WLAN to AP 110. Network 100 also includes several WLANSTAs shown as STA2 (122) and STA3 (123).

FIG. 1B is a timing diagram that depicts activity of the combo device120 shown as STA1, and AP 110, including the mode that is active as afunction of time, showing overlapping of A-MPDU packet transmission fromAP 110 intended for receipt by combo device 120 into a BT activeinterval for combo device 120. A-MPDU packets comprise a plurality ofmedium access control layer (MAC) frames. Overlap can occur because thetransmission of a long A-MPDU by the AP 110 started before a CTS2Selfframe is transmitted by the combo device 120, or because the combodevice 120 may want to transmit an A-MPDU packet in the uplink (e.g., toAP (110)). SIFS shown stands for short interframe spacing.

Since the transmission of a block acknowledgement (BA) response expectedfrom the combo device to the A-MPDU packet falls within the BT activityinterval of the combo device 120, a BA response cannot be transmitted bythe combo device 120. The AP 110 will thus not receive anacknowledgement from the combo device 120 and will therefore assume thatthe A-MPDU packet that was transmitted to the combo device 120 was notreceived (lost). AP 110 will try to retransmit the same A-MPDU packet ata later time to combo device 110 which reduces the transmission rate andin some instances can result in dropped data.

SUMMARY

Disclosed embodiments include aggregated packet designs for wirelesscommunications that feature enhanced packet aggregation for improvingperformance in coexisting wireless networks that comprise (i) acombination (combo) device that communicates over both first and secondwireless networks and at least (ii) a first wireless device thatcommunicates over a first wireless network. The first wireless devicecan act as an AP for the first wireless network, or simply be anotherSTA (e.g., for a peer to peer connection arrangement).

Disclosed packet aggregators generate frame aggregated packets fortransmission over the first network that include a plurality of datapackets and a dummy packet or spoofing so that the frame aggregatedpacket is extended in time or indicates an extension sufficient tooverlap a Tx time interval or Rx time interval for the second network.The combo device transmits or receives an acknowledgement (ACK) on thefirst network during the activity interval for the second wirelessnetwork.

In one embodiment the first wireless device can include a disclosedpacket aggregator. In this embodiment, the duration of transmittedaggregated packets from the first wireless device allows the combodevice to send the ACK over the first network during the second networkactivity interval, typically during a non-operation time (referred toherein as a remaining time) for the second wireless network. In anotherembodiment the combo device includes a disclosed packet aggregator. Inthis embodiment the combo device receives an ACK over the first wirelessnetwork during the activity interval for the second wireless network.

The extended length for disclosed aggregated packets such as an A-MPDUframe helps ensure successful reception of an immediate block ACK (BA)frame, to improve first network performance without sacrificing secondnetwork performance. Disclosed packets can also improve performancewithout use of CTS2Self frames for protection, since the duration of anaggregated packet can protect the second network (e.g., BT) interval andnot let avalanche occur. In certain embodiments both the first wirelessdevice and combo device can include a disclosed packet aggregator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts a known wireless network including a first network APshown as a WLAN AP, and a combo device that communicates with AP of thefirst network and over a second overlapping network shown as BT to a BTslave, while FIG. 1B depicts overlapping of an A-MPDU packettransmission from the AP and the BT active interval of the combo device.

FIG. 2A is a block diagram depiction of an example coexisting wirelessnetwork according to an example embodiment, including a wireless combodevice including a disclosed packet aggregator and a first wirelessdevice communicating via the first wireless network, and anotherwireless device communicating via the second wireless network, where thecombo device has separate antennas for the respective networkcommunications.

FIG. 2B is a block diagram depiction of an example coexisting wirelessnetwork according to an example embodiment including a wireless combodevice including a disclosed packet aggregator and a first wirelessdevice communicating via the first wireless network, and anotherwireless device communicating via the second wireless network, where thecombo device has a single antenna for the respective networkcommunications.

FIG. 3 is an example timing diagram showing WLAN and BT activity where aWLAN AP transmits an A-MPDU packet including a dummy packet portion to acombo device, according to an example embodiment.

FIG. 4 shows an example timing diagram for another arrangement where aWLAN AP transmits an A-MPDU packet including a dummy packet portion to acombo device, according to an example embodiment.

FIG. 5 shows an example timing diagram for a wireless STA transmittingover a WLAN network including a dummy packet portion shown as an emptypacket that spoofs the duration of the end of the A-MPDU packet toextend to the remaining (Rem) time in the BT Tx interval of a combodevice, according to an example embodiment.

FIG. 6 shows an example timing diagram for a wireless STA transmittingover a WLAN network a dummy packet portion shown as an empty packet thatspoofs the duration of the end of the A-MPDU packet to extend to the endof the BT Tx packet (pck) duration, followed by transmission of anadditional MPDU packet that arrives during a remaining (Rem) time in theBT Tx interval of a combo device, according to an example embodiment.

FIGS. 7 and 8 depict examples of fields in the PHY preamble of theaggregated IEEE 802.11n packet that can be modified to account fordisclosed extended packet length duration, according to exampleembodiments.

DETAILED DESCRIPTION

Example embodiments are described with reference to the drawings,wherein like reference numerals are used to designate similar orequivalent elements. Illustrated ordering of acts or events should notbe considered as limiting, as some acts or events may occur in differentorder and/or concurrently with other acts or events. Furthermore, someillustrated acts or events may not be required to implement amethodology in accordance with this disclosure.

Disclosed embodiments include aggregated packet designs for wirelesscommunications that improve performance of coexisting wireless networksthat include at least one combo device. For example, when the firstnetwork comprises a WLAN and the second network comprises BT, andaggregated packets such as A-MPDU or A-MSDU packets are used for theWLAN communications, the duration of such conventional aggregatedpackets can overlap with BT operation for the combo device that cancause efficiency loss and packet drops for first network communications.Disclosed embodiments include having the wireless device(s) thattransmits the aggregated packets over the first network extend thelength of the first network packet communications by including a dummypacket or spoofing so that frame aggregated packet is extended orindicates an extension sufficient to overlap the Tx time interval or Rxtime interval on the second wireless network. Disclosed packetaggregation helps ensure successful transmission and/or reception of anACK frame by the combo device, and can improve first network throughputwithout sacrificing second network performance.

The paragraph below clarifies spoofing, adding gaps and dummy packets asused herein for extending the length of packet communications, withreference to an example A-MPDU packet. An aggregated MPDU packet has twoPHY preambles, one legacy and the other high throughput (HT) preamble.The legacy portion always indicate a data length and a data rate suchthat the time duration of the packet=data_length/data_rate. In somearrangements, even though the aggregated packet might be shorter (intime), the legacy portion may indicate a longer packet in time; hencespoofing. If one or more dummy packets are added, then the legacyportion of the preamble performs the same function:packet_in_time=data_length/data_rate. However, if gaps are added; thereal packet duration is smaller than data_length/data_rate, hence,spoofing. However, spoofing in this case can also be done at the HTpreamble portion. So both, legacy and HT preambles are indicating a datalength such that it covers the gaps that needs to be introduced (it isnoted that the data rate and data length in legacy and HT preamble neednot be the same).

FIG. 2A is a block diagram depiction of an example coexisting wirelessnetwork 200 according to an example embodiment. Network 200 includes awireless combination (combo) device 210 including a first wirelesstransceiver 212 communicating via a first wireless network and a secondwireless transceiver 214 communicating via a second wireless networkthat overlaps the first wireless network. Transceiver 212 is coupled toantenna 223, and transceiver 214 is coupled to antenna 224. In anotherembodiment described below relative to FIG. 2B, the respectivetransceivers 212, 214 share a common antenna.

Combo device 210 includes a first processor 241 (e.g., a digital signalprocessor) that is coupled to the first transceiver 212, and a secondprocessor 242 coupled to the second transceiver 214. First processor 241implements a packet aggregator 232 function using a disclosed packetaggregator algorithm stored in memory 219 based on timing controlinformation provided by controller 248, which in one embodiment is acentral processing unit (CPU). Although controller 248 is shown locatedat the combo device 210, the controller can generally be locatedanywhere in the network 200, as long as its information can be receivedand interpreted correctly by the devices in the network 200. Controller248 conveys timing information to the devices in each network, and isshown in FIG. 2 coupled to first processor 241 of combo device 210 toprovide timing control information generally by a wired connection forcombo device 210, and is coupled to antenna 223 for transmitting timinginformation over the first network to wireless device 270.

Wireless device 270 communicates via the first wireless network and isconfigured as an AP for network 200. However, as noted above, wirelessdevice 270 can simply be another STA in the first network (e.g., for apeer to peer connection arrangement). Wireless device 270 comprises atransceiver 271, an antenna 272 and processor 276. Processor 276implements a packet aggregator 232 function using a disclosed packetaggregator algorithm stored in memory 219 based on timing informationprovided by controller 248 received via antenna 272. A second firstwireless device 275 that includes transceiver 278 communicates via thesecond wireless network and includes antenna 277.

FIG. 2B is a block diagram depiction of an example coexisting wirelessnetwork 250 according to an example embodiment, including the wirelesscombo device shown in FIG. 2A modified to have a single antenna 253 forthe respective network communications shown as combo device 210′, alongwith the first wireless device 270, and other wireless device 275 shownin FIG. 2A. Having a single antenna, time multiplexing is generally usedand combo device 210′ cannot generally simultaneously transmit/receivein both networks.

In one particular embodiment the first wireless network comprises a WLANand the second wireless network comprises a WPAN. Example WPANs includeBT, as well as Zigbee and LTE which use the ISM band.

FIGS. 3-6 described below are for the particular coexisting networkarrangement comprising WLAN and BT, with the understanding thatdisclosed embodiments are in no way limited to this particularcoexisting network arrangement. FIG. 3 is an example timing diagramshowing WLAN and BT network activity where a WLAN AP transmits an A-MPDUpacket including a dummy packet portion to a combo device, according toan example embodiment.

The BT active interval is seen to be split into the BT transmit (BT Tx)and BT receive (BT Rx) intervals. Depending on which device is themaster or the slave for BT, the Rx interval can be before Tx interval.As shown in FIG. 3, for the BT Tx interval, the duration of the BTpacket does not always occupy the full BT Tx interval. Hence, theunused/remaining (Rem) time in the BT Tx interval can be used by thecombo device in disclosed embodiments to Rx or Tx packets over the WLANnetwork. Thus, if the combo device is receiving an aggregated packet(e.g., A-MPDU packet), it can reply with a BA response provided that itsresponse does not overlap with its BT Rx time. The portion of the A-MPDUpacket at the time the combo device is transmitting the BT packet asshown in FIG. 3 is a dummy packet (e.g., data with stuffed bits) that asshown in FIG. 3 completely fills the TX packet duration.

The dummy packet need not have any particular content, and can be empty(no packet). The dummy packet is described as follows for A-MPDU packetswhen not empty:

(i) If the length to be covered by the dummy packet is longer than whatmaximum_size_per_mpdu_packet/data_rate indicates, then the dummy packetcan be a combination of packets such that the total duration is the sameas the duration needed to be covered. In that scenario, the packetdelimiter which gives the packet length should generally be present foreach of these packets.ii) If the length to be covered by the dummy packet is shorter than whatmaximum_size_per_mpdu_packet/data_rate indicates, then, there willgenerally be a single packet where the packet delimiter indicates thepacket length.iii) The content of the packet (or packets) comprising the dummy packetcan be all zeros or all ones. In that case, the packet decoding can beskipped.

It is noted that the packet/data_rate is given in the PHY preambleheader carrying the aggregated frame. Each frame/packet is generallyseparated by a packet delimiter which also has a length information ofthe following packet.

The duration of the dummy packet shown in FIG. 3 can be utilized by theAP as it sees fit. For example, the AP can start transmissions duringthe dummy packet interval to other STAs in the network. Note that afterreceiving the BA response from the combo device the AP can also continuewith transmission of other frames/packets to the combo device. This ispossible if both first and second transceivers for WLAN and BT,respectively, each have their own antenna. The first and secondtransceivers for WLAN and BT, respectively, can also use a singleantenna. The device may need to switch to WLAN to transmit BA to the AP;then, go to BT mode again just before BT Rx starts. During this time,the AP can still transmit a packet to the device, provided that thereply comes during allowed WLAN Tx time.

FIG. 4 shows an example timing diagram for another arrangement where aWLAN AP transmits an A-MPDU packet including a dummy packet portion to acombo device, according to an example embodiment. Note that in FIG. 4,the A-MPDU transmitted by the AP can last up to the near end of the BTRx packet duration, if both WLAN and BT on the combo device each haveseparate antennas. If both WLAN and BT on the combo device share thesame antenna, then the last MPDUn+1 can be a dummy packet. A dummypacket can be transmitted if the length of MPDUn is almost the same asthat of remaining BT Tx time and a BA cannot be sent by the combo devicewithout overlapping with BT Rx time interval. Also note that in FIG. 3,the AP may choose not to transmit MPDUn and can simply transmit a dummypacket as shown, or set the duration field of the packets to account forthe dummy packet length (see the below described combo device behaviorfor transmitting A-MPDU packets. In some other scenarios, where Tx/Txoperation is allowed for dual antenna combo device operation, then thecombo device can also transmit a BA frame during the BT Tx pck durationinterval.

If the duration of the transmitted BT packet by the combo device fullyoccupies BT Tx interval, then A-MPDU packets transmitted from the AP canlast up to the time to ensure that a BA response can be sent by thecombo device. In this case, the duration will be up to the end ofreceived BT packet less the SIFS. Thus, the length of the dummy packetin FIG. 4 can be extended to cover the full BT Tx interval and aconventional MPDU packet can be appended to the A-MPDU and receivedduring BT Rx interval with either the WLAN and BT transceivers havingseparate antennas or a shared LNA for single shared antenna embodiments,or the length of the dummy packet can extend to cover BT Tx and BT Rxpck duration interval less the SIFS. If both BT Tx and BT Rx intervalsare fully occupied, then the dummy packet (or spoofing portion) of theA-MPDU packet duration) can be extended until the last of BT activeinterval less the SIFS.

As noted above, the combo device can include a disclosed packetaggregator. For the combo device transmitting an aggregated packet suchas an A-MPDU for which a BA response from the AP may fall within thecombo device's BT activity interval, the combo device can spoof toextend the length of the aggregated packet so that the BA is sent by theAP in an unused (Rem) BT Tx interval, or it is received during the BT Rxinterval if the unused (Rem) BT Tx interval is zero.

Spoofing of the length of the aggregated packet as disclosed herein canbe done in the physical (PHY) layer preamble (PLPC) of the packet. Thetwo fields that can define packet duration are one for the legacydevices (IEEE 802.11 b,a,g) and the other one is for high throughput(HT) stations (or IEEE 802.11n capable devices). Both of these fieldsare generally configured to indicate the same packet duration. While thelegacy portion that indicates the duration can spoof the time and thedata rate, the HT portion generally should provide the correct data rateused. Hence, for A-MPDU packet embodiments, a wireless STA such as acombo device can choose to spoof the length of the A-MPDU packet andstart resuming A-MPDU transmission once allowed, or spoof the length ofthe packet until the time interval that a BA response can be receivedfrom the AP without resuming A-MPDU transmission even if allowed.

It is noted that spoofing, as described above, can be used by the AP foraggregated packets as well. FIG. 5 shows an example timing diagram for awireless STA transmitting over a WLAN network a dummy packet portionshown as an empty packet portion that spoofs the duration of the end ofthe A-MPDU packet to extend the remaining (Rem) time in the BT Txinterval of a combo device, according to an example embodiment. FIG. 6shows an example timing diagram for a wireless STA transmitting over aWLAN network a dummy packet portion shown as an empty packet portionthat spoofs the duration of the end of the A-MPDU packet to extend tothe end of the BT Tx pck duration followed by transmission of anadditional MPDU packet that arrives during a remaining (Rem) time in theBT Tx interval of a combo device, according to an example embodiment.For the shared antenna case, the empty spoofed time interval (where nopacket is sent) can be implemented. However, if WLAN and BT have theirown antenna, a dummy packet could alternatively be transmitted insteadof the spoofed time interval. It is noted that if Tx/Tx operation isallowed, then the spoofed time duration where no packet is sent could beused to transmit a regular MPDU that is part of the A-MPDU.

FIGS. 7 and 8 depict examples of fields in the PHY preamble of theaggregated IEEE 802.11n packet that can be modified to account fordisclosed extended packet length duration, according to exampleembodiments. In the L-SIG and HT-SIG1 fields shown in FIGS. 7 and 8,respectively, only the rate and the length of the packet is configuredto show the end of the transmitted frame (or spoofed frame). While L-SIGis generally uses a different rate than what the A-MPDU packet is using,in the HT-SIG1 field the rate can be the one used, however, the lengthof the packet will be different. Hence, the following relationship canbe used to determine packet length:Length_data_L-SIG/rate_L-SIG=Length_data_HT-SIG1/rate_HT-SIG1(BW_Factor)where BW_Factor relates to the rate found in the HT-SIG1 to theappropriate data rate based on the bandwidth being used.

Many modifications and other embodiments of the invention will come tomind to one skilled in the art to which this invention pertains havingthe benefit of the teachings presented in the foregoing descriptions,and the associated drawings. Therefore, it is to be understood thatembodiments of the invention is not to be limited to the specificembodiments disclosed. Although specific terms are employed herein, theyare used in a generic and descriptive sense only and not for purposes oflimitation.

Many modifications and other embodiments of the invention will come tomind to one skilled in the art to which this invention pertains havingthe benefit of the teachings presented in the foregoing descriptions,and the associated drawings. Therefore, it is to be understood that thescope of the invention is not to be limited to the specific embodimentsdisclosed. Although specific terms are employed herein, they are used ina generic and descriptive sense only and not for purposes of limitation.

We claim:
 1. A method of wireless communications, comprising:transmitting a frame aggregated packet comprising a plurality of datapackets and a dummy packet, so that said frame aggregated packetindicating an extension sufficient to overlap a Tx time interval or a Rxtime interval; receiving an acknowledgement (ACK) on a first networkduring an activity interval for a second wireless network, whereinduring said activity interval for said second wireless network at leastone of (i) said transmit (Tx) time interval is longer in duration than aTx packet duration and (ii) said receive (Rx) time interval is longer induration than a Rx packet duration to provide a remaining time andwherein said dummy packet completely filling said Tx packet duration orsaid Rx packet duration.
 2. The method of claim 1, wherein said ACK iscommunicated during a portion of said remaining time.
 3. The method ofclaim 1, wherein transmitting a frame aggregated packet comprising aplurality of data packets and said dummy packet is spoofing.
 4. Themethod of claim 3, further comprising performing Tx activities during aduration of said spoofing.
 5. The method of claim 3, wherein at leastone of said plurality of data packets follows said dummy packet.
 6. Themethod of claim 5, further comprising transmitting a final one of saidplurality of data packets during said Rx packet duration or said Txpacket duration.
 7. The method of claim 3, wherein said spoofingcompletely fills said Tx packet duration or said Rx packet duration, andfurther comprising receiving said ACK during said remaining time.
 8. Themethod of claim 3, wherein said spoofing completely fills said Tx packetduration or said Rx packet duration, and further comprising receivingsaid ACK during said Tx time interval.
 9. The method of claim 3, whereinsaid spoofing completely fills said Tx packet duration or said Rx packetduration, and further comprising receiving said ACK during said Rx timeinterval.
 10. The method of claim 3, further comprising transmitting afinal one of said plurality of data packets after said spoofing andduring said remaining time.
 11. The method of claim 1, wherein saidfirst wireless network is a wireless local area network (WLAN) and saidsecond wireless network comprises a wireless personal area network(WPAN).
 12. The method of claim 11, wherein said WPAN operates accordingto a Bluetooth (BT) network protocol.
 13. A wireless combination device,comprising: a first wireless transceiver coupled to an antennaconfigured for communication via a first wireless network; a secondwireless transceiver configured for communication via a second wirelessnetwork; and a packet aggregator coupled to said first wirelesstransceiver that configures frame aggregated packet for at least aportion of activities on said first wireless network, wherein said frameaggregated packet includes a plurality of data packets and a dummypacket or spoofing extending in time sufficient to overlap a Tx timeinterval or Rx time interval for communications occurring over saidsecond wireless network) wherein said first wireless network and saidsecond wireless network are overlapping networks.
 14. The wirelesscombination device of claim 13, wherein said wireless combination deviceperforms Tx or Rx activities on said second wireless network during aduration of said dummy packet or said spoofing.
 15. The wirelesscombination device of claim 13, further comprising a controller thatconveys timing information to devices on said first wireless network andto devices on said second wireless network.
 16. The wireless combinationdevice of claim 13, wherein said first wireless network is a wirelesslocal area network (WLAN) and said second wireless network comprises awireless personal area network (WPAN).
 17. The wireless combinationdevice of claim 16, wherein said WPAN comprises a Bluetooth (BT)network.